Wednesday, June 13, 2007

Vezina Trophy: Strength of Teammates

Strength of teammates is an important consideration for goaltenders. The stronger the team around them, the more likely they are to win games. A strong defensive team is also likely to benefit the goalie's performance statistics, such as save percentage and goals against average.

Both New Jersey and Vancouver took slightly more shots than they gave up. New Jersey took fewer shots and allowed fewer. The difference was even greater once you factor in the differences between the Eastern and Western Conferences. The Canucks took 0.3 more shots and gave up 0.6 shots more than their conference average, pretty much an average team in the defensive West. The Devils took 1.5 fewer shots per game than their conference average, and gave up 2.2 fewer, indicating that their style of play contrasted greatly with the rest of their conference rivals.

Both taking and allowing fewer shots than average suggests that the Devils intentionally play a lower-scoring type of game, and that one of the reasons they don't score many goals is because of that style of play. New Jersey scored a few more goals than they allowed in all three periods, which indicates that they only scored as many goals as they needed. A defensive style of play is particularly obvious in their first period results. Whereas second and third period scoring is often driven by the score at the time, the first period always begins 0-0. That makes the chosen style of play more decisive than the particular game situation. New Jersey's chosen style of play was clearly defensive: they scored the second fewest goals in the league in the first period, and gave up the fewest.

On ice statistics also support the idea that New Jersey intentionally plays a low-scoring game. Centers Gomez, Madden, and Elias all averaged about 19 minutes a game. Madden actually played more than either Gomez or Elias at even-strength, averaging 15:24 per game. Heavy use of their checking line reduces New Jersey's goal-scoring while simultaneously reducing the goals against. For Vancouver, their top two centers Henrik Sedin and Brendan Morrison averaged 18 minutes per game, while Ryan Kesler averaged 16, and Josh Green 11.

New Jersey was also better at coming from behind when trailing after one period than Vancouver was, which is a sign of offensive ability since even a defensive team has to attack when they are behind. The Devils were 9-11-4 when trailing after one, the Canucks 6-15-4. New Jersey was also more effective at closing out leads than Vancouver was, winning 31 of 34 games they led after 2. Vancouver won 30 out of 36.

New Jersey's forwards scored 185 goals and 430 points in 2005-06. Vancouver's scored 178 goals and 459 points last season. Based on career scoring rates, New Jersey's forwards would be expected to score 2.45 goals and 5.89 points per game. Vancouver's forward line that began the season would be expected to come in at 2.20 goals and 5.48 points per game. At the deadline, the Canucks acquired Bryan Smolinski, which added a bit of scoring depth and raised the expected totals to 2.36 and 5.88, very close to New Jersey.

Perhaps the most controversial aspect of the strength of teammate debate is the argument over whether Vancouver or New Jersey has a better defensive corps. Many would say Vancouver, but a key part of that is their offensive play - Vancouver's defencemen scored 149 points this season to New Jersey's 122. From a goalie performance perspective, it doesn't matter how good the defencemen are at scoring goals, just how good they are at preventing them. To try to evaluate this, I looked at the personal goals against averages of each team's defencemen over the last 4 seasons, based on the research done at the Hockey Analysis Group.

The average goals against while they were on the ice per 60 minutes over the last 4 seasons for New Jersey's current defencemen was 3.02. For Vancouver, it was 3.60.

This season was par for the course for New Jersey's defencemen. None of them, other than rookies Andy Greene and Johnny Oduya, had personal best goals against averages this season. Paul Martin and Colin White were over their 4-year PGAA average, and Brad Lukowich was just slightly under his, despite Martin Brodeur playing much better this year than he did over the 3 previous seasons.

For Vancouver, Brent Sopel, Sami Salo, Mattias Ohlund, Lukas Krajicek, and Rory Fitzpatrick all had a lower goals against rate this season than in any of the previous 3 seasons. Other than Willie Mitchell, every Canucks defenceman was below his average personal goals-against over the last 4 seasons.

The difference appears to be mostly from goaltending. The Canucks have in years past played a more offensive style, which certainly resulted in more goals against, but last year the Canucks gave up 29.9 shots per game, and according to Ken Krzywicki had average shot quality against. This year, they gave up 28.9 shots per game with easier-than-average shot quality. That is certainly an improvement, but not a huge one. However, their team save percentage went from .900 to .920, which is a bigger reason for the increase.

Several of the Canucks defencemen weren't even with the team last year. Of all the minutes played by Canucks defencemen, 54% were by players that were with the team in 2005-06, a substantial turnover. For New Jersey, 80% of the minutes played were by players who had been with the team last year. As might therefore be expected, New Jersey's defensive performance in 2006-07 was very similar to that of 2005-06. The Devils gave up 27.9 shots per game with easier-than-average shot quality, compared to last year's 28.8 shots per game (also easier than average).

The statistics indicate that New Jersey's defence is better at goal prevention, and that the main reason for many Vancouver defencemen having career defensive years was the goaltending. Based on past scoring history, the two teams' forwards are very similar in talent. New Jersey plays a more conservative, defensive style, which is why they scored fewer goals. The two teams are similar in makeup, style and talent. Overall, there is little talent difference between these two teams to tip the scales towards one goalie or the other. Perhaps one of the biggest differences concerning teammates was that Roberto Luongo had to adjust to a new team in a new conference with a revamped defence corps, while Brodeur played on the same team and system that he always has. Perhaps that explained some of Luongo's early season troubles; if he could play an entire season in his post-Christmas form, he would certainly be the best goaltender in the NHL.